Microbial Desulfurization of Low-Grade Balochistan Coal using Bacillus licheniformis and Bacillus pumilus

Microbial Desulfurization of Low-Grade Balochistan Coal using Bacillus licheniformis and Bacillus pumilus | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Microbial Desulfurization of Low-Grade Balochistan Coal using Bacillus licheniformis and Bacillus pumilus Asif Naeem, Maqsood Ahmed, Asad Ullah, Jamal Khan, Zahid Naeem Qaisrani This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8988367/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 16 You are reading this latest preprint version Abstract Coal is an abundant source of energy; however, the use of Pakistani coal is limited due to its high sulfur content, causes environmental and health issues. Hence, pre-combustion desulfurization of coal is imperative for quality enhancement. The present study investigates the microbial desulfurization of coal from the Balochistan mine by using local bacterial strains, Bacillus pumilus and Bacillus licheniformis , isolated from the same coal mine, for their sustainability, adaptability, and local availability. Batch incubation experiments with a coal particle size of 75 and 150 µm and incubation periods of 7 and 14 days were conducted to evaluate the effect of particle size and incubation period on the sulfur removal efficiency. Proximate and ultimate analyses were carried out using standard CHNS methods, while XRD was used to determine changes in the composition and structure before and after treatment. The results showed that microbial treatment increased calorific value, specifically at smaller particle sizes and longer incubation periods. The maximum sulfur removal achieved by B. licheniformis was 32.73% and 41.06%, whereas B. pumilus exhibited a removal of 20.75% and 33.48% at a particle size of 75 µm after 7 and 14 days, respectively. These findings demonstrate that bio-desulfurization using indigenous microorganisms is an effective and environmentally sustainable approach for upgrading low-grade Pakistani coal for cleaner energy production. Microbial desulfurization Bacillus licheniformis Bacillus pumilus Low-grade coal Sulfur removal efficiency Sustainable energy production Full Text Additional Declarations No competing interests reported. Cite Share Download PDF Status: Under Review Version 1 posted Editorial decision: Revision requested 23 Mar, 2026 Reviews received at journal 21 Mar, 2026 Reviews received at journal 20 Mar, 2026 Reviews received at journal 06 Mar, 2026 Reviewers agreed at journal 06 Mar, 2026 Reviewers agreed at journal 05 Mar, 2026 Reviewers agreed at journal 05 Mar, 2026 Reviewers agreed at journal 05 Mar, 2026 Reviewers agreed at journal 04 Mar, 2026 Reviewers agreed at journal 04 Mar, 2026 Reviewers agreed at journal 03 Mar, 2026 Reviewers agreed at journal 03 Mar, 2026 Reviewers invited by journal 03 Mar, 2026 Editor assigned by journal 03 Mar, 2026 Submission checks completed at journal 03 Mar, 2026 First submitted to journal 27 Feb, 2026 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-8988367","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":601940080,"identity":"a7e3530e-cfe3-42b0-825a-fbe6b454722b","order_by":0,"name":"Asif Naeem","email":"","orcid":"","institution":"Balochistan University of Information Technology, Engineering and Management Sciences","correspondingAuthor":false,"prefix":"","firstName":"Asif","middleName":"","lastName":"Naeem","suffix":""},{"id":601940081,"identity":"8cb28af9-caf8-43e6-b71d-2427e349fff3","order_by":1,"name":"Maqsood Ahmed","email":"","orcid":"","institution":"Balochistan University of Information Technology, Engineering and Management Sciences","correspondingAuthor":false,"prefix":"","firstName":"Maqsood","middleName":"","lastName":"Ahmed","suffix":""},{"id":601940082,"identity":"7ab78d0b-dffa-42ad-bd1f-b4ef9cb1987a","order_by":2,"name":"Asad Ullah","email":"","orcid":"","institution":"Suranaree University of Technology","correspondingAuthor":false,"prefix":"","firstName":"Asad","middleName":"","lastName":"Ullah","suffix":""},{"id":601940083,"identity":"b571eb18-331e-4175-b749-1e158148f1cd","order_by":3,"name":"Jamal Khan","email":"","orcid":"","institution":"Balochistan University of Information Technology, Engineering and Management Sciences","correspondingAuthor":false,"prefix":"","firstName":"Jamal","middleName":"","lastName":"Khan","suffix":""},{"id":601940086,"identity":"dd2cca3c-a283-4c09-8fd2-d9c879ff9c03","order_by":4,"name":"Zahid Naeem Qaisrani","email":"data:image/png;base64,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","orcid":"","institution":"Balochistan University of Information Technology, Engineering and Management Sciences","correspondingAuthor":true,"prefix":"","firstName":"Zahid","middleName":"Naeem","lastName":"Qaisrani","suffix":""}],"badges":[],"createdAt":"2026-02-27 13:08:34","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-8988367/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-8988367/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":104264959,"identity":"236edc01-6b93-4c13-a697-50ac681b27ae","added_by":"auto","created_at":"2026-03-09 19:41:09","extension":"pdf","order_by":1,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":962379,"visible":true,"origin":"","legend":"","description":"","filename":"Manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-8988367/v1_covered_d936032c-dc0b-4efd-91c7-c85937581f59.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Microbial Desulfurization of Low-Grade Balochistan Coal using Bacillus licheniformis and Bacillus pumilus","fulltext":[],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":false,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":true,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":true,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"biodegradation","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"biod","sideBox":"Learn more about [Biodegradation](http://link.springer.com/journal/10532)","snPcode":"10532","submissionUrl":"https://submission.nature.com/new-submission/10532/3","title":"Biodegradation","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false},"keywords":"Microbial desulfurization, Bacillus licheniformis, Bacillus pumilus, Low-grade coal, Sulfur removal efficiency, Sustainable energy production","lastPublishedDoi":"10.21203/rs.3.rs-8988367/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-8988367/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eCoal is an abundant source of energy; however, the use of Pakistani coal is limited due to its high sulfur content, causes environmental and health issues. Hence, pre-combustion desulfurization of coal is imperative for quality enhancement. The present study investigates the microbial desulfurization of coal from the Balochistan mine by using local bacterial strains, \u003cem\u003eBacillus pumilus\u003c/em\u003e and \u003cem\u003eBacillus licheniformis\u003c/em\u003e, isolated from the same coal mine, for their sustainability, adaptability, and local availability. Batch incubation experiments with a coal particle size of 75 and 150 \u0026micro;m and incubation periods of 7 and 14 days were conducted to evaluate the effect of particle size and incubation period on the sulfur removal efficiency. Proximate and ultimate analyses were carried out using standard CHNS methods, while XRD was used to determine changes in the composition and structure before and after treatment. The results showed that microbial treatment increased calorific value, specifically at smaller particle sizes and longer incubation periods. 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These findings demonstrate that bio-desulfurization using indigenous microorganisms is an effective and environmentally sustainable approach for upgrading low-grade Pakistani coal for cleaner energy production.\u003c/p\u003e","manuscriptTitle":"Microbial Desulfurization of Low-Grade Balochistan Coal using Bacillus licheniformis and Bacillus pumilus","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2026-03-09 19:40:51","doi":"10.21203/rs.3.rs-8988367/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2026-03-23T05:56:56+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-03-22T02:25:49+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-03-20T16:56:43+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-03-06T14:19:11+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"141018275291933290308221288018158451121","date":"2026-03-06T05:33:42+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"83483006101805265628987818965478455252","date":"2026-03-06T03:19:15+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"122636646078724337024763840453962357195","date":"2026-03-06T02:32:18+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"123921734425641056160859871442232365467","date":"2026-03-06T02:05:47+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"269467924342739848310565555532321941043","date":"2026-03-04T12:56:07+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"337283921397253863823350016136122792439","date":"2026-03-04T06:12:44+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"152585121123908854294398141682876202017","date":"2026-03-04T04:34:17+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"155081133435204309962919121036071915918","date":"2026-03-04T02:25:04+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2026-03-04T01:50:42+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2026-03-03T09:45:38+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2026-03-03T09:39:18+00:00","index":"","fulltext":""},{"type":"submitted","content":"Biodegradation","date":"2026-02-27T13:05:01+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"biodegradation","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"biod","sideBox":"Learn more about [Biodegradation](http://link.springer.com/journal/10532)","snPcode":"10532","submissionUrl":"https://submission.nature.com/new-submission/10532/3","title":"Biodegradation","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false}}],"origin":"","ownerIdentity":"de5a94b2-bf7c-4d8f-8135-11166b873569","owner":[],"postedDate":"March 9th, 2026","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"under-review","subjectAreas":[],"tags":[],"updatedAt":"2026-05-05T06:10:09+00:00","versionOfRecord":[],"versionCreatedAt":"2026-03-09 19:40:51","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-8988367","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-8988367","identity":"rs-8988367","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}